Pack for heating and cooling

ABSTRACT

A thermal pack holding a pair of mixable components, one of which is flowable, to produce a desired exothermic or endothermic reaction is disclosed. The pack is formed of a flexible sheet having two compartments, one for each of the components, separated by a frangible barrier arranged to be broken to enable the components to mix. In one embodiment the pack includes a pair of pull tabs to enable the user to break the frangible barrier. In another embodiment the pack is folded, with the compartments juxtaposed with respect to each other, whereupon the application of pressure to the pack causes the flowable material to apply pressure to the frangible barrier to cause it to rupture.

BACKGROUND OF THE INVENTION

This invention relates to heating or cooling packs and more particularly to thermal packs for holding separate ingredients, which when mixed produce either an exothermic or endothermic reaction.

Heating or cooling packs are known for use in a variety of applications including therapy for muscular injury or circulatory problems or heating or cooling food. Such packs typically hold two reactants in separate compartments in the pack until ready for use, at which time a barrier or some other structure separating the compartments is broken or ruptured so that the reactants can be mixed together to produce an endothermic or exothermic reaction. Examples of such thermal packs are disclosed in the following U.S. Pat. Nos.: 3,913,559; 5,611,329; 5,967,308; 6,289,887; and 6,827,080 and in the following published patent applications: US2006/0191272 and US2006/0135016.

While the thermal packs of the prior art are generally suitable for their intended purposes, they nevertheless leave something to be desired from the standpoint of ease of use and effectiveness of operation. In particular, a need exists for a thermal pack that is constructed to facilitate the opening of the compartments holding the reaction-inducing components to effectively intermix those components and thereby produce an even heating or cooling effect across the pack. The subject invention addresses that need.

SUMMARY OF THE INVENTION

One aspect of this invention is a thermal pack holding a pair of mixable components, one of which is flowable. The pair of mixable components is arranged when mixed to produce either an exothermic or endothermic reaction for heating or cooling, respectively. The thermal pack is formed of a flexible sheet material having a first panel, a second panel, and a pair of pull tabs. One of the pull tabs is connected to the first panel and the other of the pair of pull tabs is connected to the second panel. The first panel is secured to the second panel to form a first compartment and a second compartment located between the panels. The first compartment is isolated from the second compartment by a frangible barrier located between the panels. The first compartment is arranged for holding a first one of the pair of mixable components. The second compartment the arranged for holding a second one of the pair of mixable components. The pair of pull tabs is coupled to the frangible barrier and is arranged to be grasped and pulled apart to break the frangible barrier, whereupon the mixable components can be mixed together to produce the desired exothermic or endotheimic reaction.

Another aspect of this invention is a thermal pack for holding a pair of mixable components like described above. The thermal package of this aspect of the invention is formed of a flexible sheet material having a first panel and a second panel. The first panel is secured to said second panel to form a first compartment and a second compartment. The first compartment is isolated from the second compartment by a frangible barrier located between the panels. The first compartment is arranged for holding a first one of said pair of mixable components. The second compartment is arranged for holding a second one of the pair of mixable components. The second one of the pair of mixable components is flowable, e.g., is a liquid. The thermal pack is folded so that the first and second compartments are disposed overlying each other, whereupon the application of pressure to either the first or second compartment causes the second one of the mixable components to apply pressure to the frangible barrier to cause the frangible barrier to rupture, whereupon the second one of the mixable components engages and mixes with the first one of the mixable components to produce the desired exothermic or endothermic reaction.

DESCRIPTION OF THE DRAWING

FIG. 1 is a top plan view of one exemplary pack constructed in accordance with this invention for producing a desired exothermic or endothermic reaction;

FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG. 1;

FIG. 3 is a view similar to FIG. 2, but showing the pack at an initial point in its use to produce a desired exothermic or endothermic reaction;

FIG. 4 is a view similar to FIGS. 2 and 3 but showing the pack at a subsequent point in its use to produce the desired exothermic or endothermic reaction;

FIG. 5 is view similar to FIGS. 2-4, but showing the pack at a still further point in its use to produce the desired exothermic or endothermic reaction;

FIG. 6 is a top plan view, similar to FIG. 1, but showing an alternative embodiment of a pack constructed in accordance with this invention for producing a desired exothermic or endothermic reaction; and

FIG. 7 is an enlarged sectional view, taken along line 7-7 of FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the various figures of the drawing wherein like reference characters refer to like parts, there is shown at 20 in FIG. 1 one exemplary embodiment of a thermal (e.g., heating or cooling) pack constructed in accordance with this invention. It should be pointed out at this juncture that the thermal pack of this invention is arranged to produce heat or cooling, by means of two reaction-inducing components 10 and 12, which when mixed together produce the desired exothermic (for heating) or endothermic (for cooling) reaction. The components 10 and 12 in the compartments are kept isolated from each other by a frangible barrier (to be described later), which when broken enables the two components to mix to produce the desired exothermic or endothermic reaction. Preferably one of those two components is flowable, e.g., a liquid, so that when the barrier is broken the flowable component may flow into engagement with the other component to initiate the reaction. For example, if the pack 20 is to be used for heating applications, component 10 may be quick lime and component 12, water. If the pack 20 is to be used for cooling applications, component 10 may be ammonium nitrate, and component 12, water. It should be apparent to those skilled in the art that other mixable components can be used in lieu of the foregoing exemplary components. Thus, the subject invention can be used to hold any two components, which when mixed produced a desired exothermic or endothermic reaction. It is the construction and arrangement of the pack 20 for holding the components and the combination of the pack and the exothermic or endothermic reaction-producing components that constitute the subject invention, not the particular exothermic or endothermic reaction-producing components themselves.

The exemplary embodiment of the thermal pack 20 shown in FIGS. 1-5, basically comprises two compartments in the form of pouches 22 and 24 (FIG. 2). The pouches are fabricated from a pair of wall panels 26 and 28 formed of a flexible sheet material which is folded over itself as best seen in FIG. 2. The material making up the panels 26 and 28 can be either a single ply or multiple plies of any suitable conventional flexible packaging material(s). Each of the panels 26 and 28 includes an inner surface, e.g., panel 26 includes inner surface 26A and panel 28 includes inner surface 28A. The inner surfaces 26A and 28A are fusible (as will be described later) to enable confronting portions of those panels to be fused or welded together to form the pouches or compartments 22 and 24. In particular, in the exemplary embodiment shown in FIGS. 1 and 2, the panels 24 and 26 are formed of a unitary sheet of the flexible material, having a top and bottom edge. The sheet is folded as shown in FIG. 2 to form the two compartments 22 and 24 and two projecting pull tabs 30 and 32 (to be described later). The inner surfaces of the panels 26 and 28 are welded together at peripheral seal lines extending along their abutting top and bottom edges 34 and along their side edges 36 and 38. The seal lines are permanent, e.g., constitute a welded or fused joint that is resistant to being peeled or torn open. The seal lines can be formed in various conventional ways, e.g., by use of heated bars, rollers, ultrasonic welding, etc.

Any type of flexible sheet material can be used to fabricate the thermal packs of this invention, be it a sheet material of a single layer or of multiple layers. For example, one particularly effective sheet material for the thermal packs of this invention is a lamination consisting of a polyethylene film inside layer forming the surfaces 26A and 28A. The outside surface of the lamination is 48 gauge polyester film (not shown). A layer of aluminum foil (not shown) is interposed between the inside and outside layers.

As mentioned earlier the thermal pack 20 includes a frangible barrier for isolating the two compartments 22 and 24. That barrier is best seen in FIG. 1 and basically comprises a transverse seal line 40 that includes a portion that can be readily peeled apart. In particular, the seal line 40 is provided across the portion of the pack slightly below the seal 34. The seal line 40 is a fused or welded line that joins the inner surface 28A of the portion of the panel 28 forming the compartment 22 to the inner surface 26A of the portion of the panel 26 forming that compartment. In order to make a portion of the seal line 40 frangible, a patterned peelable coating 42, e.g., polyethylene EVA copolymer with talc, is applied to either of the abutting surfaces at the seal line 40 as best seen in FIG. 1. The frangible barrier of this invention can be formed in various other ways, if desired, providing that the resulting construction can be readily opened by pulling the panel portions forming the barrier apart. To that end, the thermal pack of this invention includes the heretofore mentioned pull tabs 30 and 32.

The pull tab 30 basically comprises the portion of the pack contiguous with the seal line 34 and is composed of the contiguous and abutting portions of the panel 26. The pull tab 32 comprises an internally folded portion of the panel 28 located at the interface of the compartments 22 and 24. When the pack is in its normally stowed or folded condition, like shown in FIGS. 1 and 2, the two compartments are disposed parallel and confronting each other with the pull table 32 disposed therebetween. The pull tab 30 extends outward from the edge of the folded pack in a plane substantially coplanar with the pull tab 30 when the pack is in its folded state. With the package in this state the two compartments 22 and 24 are isolated from each other by the frangible barrier, i.e., the peelable portion 42 of the seal line 40.

By manipulating the pack as will be described in detail later, the user of the pack can grasp the two pull tabs 30 and 32 to pull them apart, which will break, i.e., peel open, the frangible barrier, thereby providing a communicating passageway between the two compartments through which the flowable component can flow to engage and mix with the other component to produce the desired exothermic or endothermic reaction. Before describing the usage of the thermal pack 20 a further discussion of the two compartments 22 and 24 and their contents, 10 and 12, respectively, is in order.

As mentioned earlier one of the compartments is arranged to hold a flowable material, e.g., water in the case of a hot pack making use of quick-lime as the other exothermic-reaction inducing component. In the embodiment of the thermal pack 20 shown that compartment is the compartment 24. The other compartment 22, in the case of a quick-lime/water exothermic pack, serves to hold the quick-lime component 10. Since the quick-lime is dry particulate or powder material, it may tend to clump in the compartment 22 so that there may not be complete mixing of the water with it, thereby producing an uneven exothermic reaction. To overcome this potential problem and in accordance with another aspect of this invention, the dry particulate or powdery component 10 is preferably dispersed into separate portions, each housed in a respective pocket of a compartmentalized (e.g., quilted) insert 44. The insert is itself located in the compartment or pouch 22 of the pack 20.

The insert 44 may be formed of one or two sheets of a porous material, e.g., filter paper, which are sealed together, e.g., heat sealed or joined by an adhesive, along various seal lines to form a quilted body having plural pockets 46 therein. A portion of the dry component 10 is located in each pocket 46 to disperse it throughout the compartment 22. Since the material making up the walls of the insert 44 is porous, when the water 12 enters into the compartment 22 through the broken barrier 42, it can readily reach virtually all of the quick-lime at the same time, thereby resulting in an exothermic reaction that is spread evenly across the entire compartment 22.

The operation of the thermal pack 20 to produce heat or to provide cooling will now be described with reference to FIGS. 3-5. In particular, the thermal pack 20 is unfolded from its folded state, shown in FIG. 1, to the state shown in FIG. 3, and from that state to the state shown in FIG. 4, whereupon the two pull tabs 30 and 32 are fully exposed so that they can be readily grasped by the user. By grasping each of those tabs and pulling them apart, the peelable seal forming the frangible barrier will delaminate or separate as shown in FIG. 5, whereupon the water 12 can flow down the pack through the now broken barrier and into the compartment 22, where it engages and surrounds the insert 44. The water can then readily penetrate through the porous material making up the walls of the insert 44 to mix with the quick lime 10 in the insert's various pockets 46, thereby initiating the exothermic producing reaction. Once the exothermic reaction (or endothermic reaction, as the case may be if endothermic reaction-inducing components are used) is initiated, the pack can be folded again to the state like shown in FIG. 1 and the folded pack then applied to a portion of a person or animal for therapeutic purposes.

If desired, the pack 20 may include another compartment (not shown) formed of a flexible material and located adjacent the compartment 22, and in which some item or product to be heated or cooled is located. For example, the pack may include an adjacent compartment in which a paper towel, wet wipe or some food product is located. Thus, when the exothermic or endothermic reaction is initiated it either heats/cools the item/product located in the adjacent compartment. The heated or cooled item/product can then be removed from its compartment for use. To facilitate the removal of the heated or cooled item/product the thermal pack 20 may include some means, e.g., tear notches (not shown) or a tear strip (not shown), which enable the compartment in which the heated/cooled item/product is located to be opened to remove it for use.

Referring now to FIGS. 6 and 7, the construction of an alternative embodiment of a thermal pack 100 of this invention will now be described. That thermal pack is similar in several respects to the thermal pack 20. Thus, in the interest of brevity the common components of the thermal pack 100 with the thermal pack 20 will be given the same reference numbers, and the details of the construction and arrangement of those components will not be reiterated. Thus as can be seen the thermal pack 100 basically comprises two compartments in the form of pouches 102 and 104, for holding the reaction-inducing components 12 and 10, respectively, therein. Preferably the component 10 is itself disposed in an insert 44, like that described heretofore, but such an arrangement is not mandatory in the embodiment 100 or in the embodiment 20.

The compartments 102 and 104 of the thermal pack 100 are fabricated from a pair of wall panels 106 and 108, each formed of a flexible sheet material, like that forming the panels of thermal pack 20. The panel 106 is folded over itself as best seen in FIG. 7 so that its top and bottom edge portions are juxtaposed with respect to each other and with its side edge portions also juxtaposed with respect to each other. The panel 108 is interposed between the folded over portions of the panel 106 so that the top edge portion of the panel 108 is interposed between the juxtaposed top and bottom edge portions of the folded panel 106 and with the side edge portions of the panel 108 interposed between the juxtaposed side edge portions of the folded panel 106. Those edge portions are welded together along a peripheral seal line made up of a top seal line 110 (FIG. 6) and a pair of side seal lines 112 and 114. The seal lines are permanent, e.g., constitute a welded or fused joint that is resistant to being peeled or torn open. The seal lines can be formed in various conventional ways, e.g., by use of heated bars, rollers, ultrasonic welding, etc.

The lower portion of the panel 108 is secured, e.g., welded, to the two overlying folded portions of the panel 106 by a transverse seal line 116, thereby forming the two compartments 102 and 104. The seal line 116 thus forms a barrier between the two compartments 102 and 104 from each other. Like the barrier 40 described above, the barrier 116 is constructed to be frangible so that it can be readily broken to enable the reaction inducing components 10 and 12 in the two compartments 102 and 104 to mix. To that end, a patterned peelable coating 118, e.g., polyethylene EVA copolymer with talc, is applied to either of the abutting surfaces at the seal line 116 as best seen in FIG. 6. The frangible barrier of the thermal pack 100 can be formed in various other ways, if desired, providing that the resulting construction can be readily broken, by the application of a hydraulic force to the barrier, as will be described hereinafter.

In particular, the barrier 116 is designed so that when pressure is applied to the thermal pack, a hydraulic force is produced and propagated through the liquid component, e.g., water, 12 to act against the barrier 116 so that the peelable coating 118 thereat delaminates or peels apart, thereby rupturing the barrier. The water can then flow into the compartment 104, thereby mixing with the component 10, e.g., the quick-lime, located in the plural pockets 46 of the insert 44, to initiate the desired exothermic reaction.

The application of pressure to the compartment 104 can be achieved by disposing the pack 100 on a surface in its folded state, as shown in FIG. 6, and then pressing on whichever compartment 102 or 104 is facing upward. This force will then be propagated to the water 12 in the compartment causing it to bear against the frangible barrier until the barrier bursts at which time the water will flood the compartment 104 holding the quick-lime 10.

In order to facilitate the rupturing of the barrier 116 it is preferably shaped so that the hydraulic force produced on it will be concentrated at one portion to cause it to begin to open thereat, with minimal applied force, and then to propagate along the length of the interface between barrier 116 and the patterned peelable coating 118. To that end, the central portion 120 of the transverse seal line 116 at the interface with the peelable coating is of a tapering shape, e.g., is generally V-shaped, tapering in the direction toward the compartment 102 (toward seal line 110). As should be appreciated by those skilled in the art, other arrangements to concentrate the force at a point on the frangible barrier can be used in lieu of the V-shaped seal portion.

As should be appreciated by those skilled in the art, the thermal packs of this invention are simple in construction, can be fabricated at low cost, yet are very easy to use and enable the quick, effective and even mixing of the reaction-producing components.

Without further elaboration the foregoing will so fully illustrate our invention that others may, by applying current or future knowledge, adopt the same for use under various conditions of service. 

1. A thermal pack holding a pair of mixable components, one of which is flowable, said pair of mixable components being arranged when mixed to produce either an exothermic or endothermic reaction for heating or cooling, respectively, said thermal pack being formed of a flexible sheet material having a first panel, a second panel, and a pair of pull tabs, one of said pair of pull tabs being connected to said first panel, the other of said pair of pull tabs being connected to said second panel, said first panel being secured to said second panel to form a first compartment and a second compartment located between said panels, said first compartment being isolated from said second compartment by a frangible barrier located between said panels, said first compartment being arranged for holding a first one of said pair of mixable components, said second compartment being arranged for holding a second one of said pair of mixable components, said pair of pull tabs being coupled to said frangible barrier and being arranged to be grasped and pulled apart to break said frangible barrier, whereupon said mixable components can be mixed together to produce the desired exothermic or endothermic reaction.
 2. The thermal pack of claim 1 wherein said second one of said mixable components is flowable and wherein said package is arranged to be oriented is a desired orientation so that when said frangible barrier is broken and said pack is in said desired orientation said second one of said mixable components flows into engagement with said first one of said mixable components.
 3. The thermal pack of claim 1 wherein said sheet material forming said first and second panels is heat sealable, and wherein said first and second panels are heat sealed together to form said first and second compartments.
 4. The thermal pack of claim 1 wherein said pack additionally comprises an insert having plural pockets, each of said pockets holding a respective portion of said first one of said mixable components therein.
 5. The thermal pack of claim 4 wherein said insert comprises a first panel and a second panel secured together to form said pockets.
 6. The thermal pack of claim 5 wherein said first and second panels of said insert are formed of flexible sheet material.
 7. The thermal pack of claim 6 wherein said flexible sheet material of said insert is porous.
 8. The thermal pack of claim 7 wherein said flexible sheet material of said insert is heat sealable.
 9. The thermal pack of claim 1 wherein said pack is normally folded so that said first and second compartments are disposed overlying each other, with one of said pull tabs being disposed between said overlying compartments, and with the other of said pull tabs extending outward from the overlying compartments.
 10. The thermal pack of claim 1 wherein said frangible barrier is formed by a peelable heat seal coating,
 11. A thermal pack for holding a pair of mixable components, said pair of mixable components being arranged when mixed to produce either an exothermic or endothermic reaction for heating or cooling, respectively, said package being formed of a flexible sheet material having a first panel and a second panel, said first panel being secured to said second panel to form a first compartment and a second compartment, said first compartment being isolated from said second compartment by a frangible barrier located between said panels, said first compartment being arranged for holding a first one of said pair of mixable components, said second compartment being arranged for holding a second one of said pair of mixable components, said second one of said pair of mixable components being flowable, said pack being folded so that said first and second compartments are disposed overlying each other, whereupon the application of pressure to either said first or second compartment causes said second one of said mixable components to apply pressure to said frangible barrier to cause said frangible barrier to rupture, whereupon said second one of said mixable components engages and mixes with said first one of said mixable components to produce the desired exothermic or endothermic reaction.
 12. The thermal pack of claim 11 wherein said sheet material forming said first and second panels is heat sealable, and wherein said first and second panels are heat sealed together to form said first and second compartments.
 13. The thermal pack of claim 11 wherein said pack additionally comprises an insert having plural pockets, each of said pockets holding a respective portion of said first one of said mixable components therein.
 14. The thermal pack of claim 13 wherein said insert comprises a first panel and a second panel secured together to form said pockets.
 15. The thermal pack of claim 14 wherein said first and second panels of said insert are formed of flexible sheet material.
 16. The thermal pack of claim 15 wherein said flexible sheet material of said insert is porous.
 17. The thermal pack of claim 16 wherein said flexible sheet material of said insert is heat sealable.
 18. The thermal pack of claim 11 wherein said frangible barrier is of a generally tapering shape, tapering in the direction from said second compartment to said first compartment.
 19. The thermal pack of claim 18 wherein said frangible barrier is generally V-shaped.
 20. The thermal pack of claim 19 wherein said frangible barrier is formed by a peelable heat seal coating. 